Pulmonary artery catheterization is an invasive procedure used in critical care to obtain detailed information about cardiac function, pulmonary circulation, and fluid status. A pulmonary artery (PA) catheter, commonly called a Swan-Ganz catheter, is inserted through a large central vein and advanced through the right side of the heart into the pulmonary artery. It is particularly useful in critically ill patients with complex hemodynamic disturbances, shock, severe heart failure, pulmonary hypertension, or during major cardiac surgery. Before insertion, the nurse explains the procedure to the patient, obtains informed consent as appropriate, assesses baseline vital signs, and reviews coagulation status and relevant investigations. Continuous electrocardiographic monitoring is required because catheter advancement through the right atrium and ventricle may produce cardiac arrhythmias. Strict aseptic technique is maintained to reduce the risk of bloodstream infection. The patient is positioned appropriately, usually supine, and the insertion site is prepared with an antiseptic solution. Common access sites include the internal